OSU improves to 13-2 overall while Kansas State is now 12-4.
Oklahoma State trailed 49-41 after Jamar Samuels hit two free throws with 9:26 left in the game but that's when Olukemi and the Cowboys – and the Gallagher-Iba crowd – came alive.
Two free throws by Olukemi, three by Keition Page and then Olukemi's conventional three-point play on a slashing drive into the paint tied the game at 49-49, and the Cowboys had the momentum.
Olukemi took control over the final nine minutes, scoring 13 points, including a shot-clock beating three-pointer with 4:44 showing on the clock to push the Cowboys lead to 63-54.
"We don't have that one guy, we don't have that James Anderson who can take a shot any time he wants, who can get hot any time. We've got different guys on our team who are going to have to step up, and J.P. is one of those guys who can create a shot. He's a guy who can score some points for us when we need a basket," said Oklahoma State head coach Travis Ford.
"JP is starting to figure out, OK I can affect this game scoring from the three, from the two, from the free-throw line and I can rebound. Maybe I do have some physical tools and maybe I haven't been getting all that I can out of them. Now he's starting to slowly get there.
"J.P., and I'd tell him if he was sitting right here, I'd be careful to praise J.P. You've got to push him and push him because I see so much potential in J.P.. He had 22 (points) and 11 (rebounds) and did terrific but I still think he's got so much more that he can do. I really do.
"I'm very high on J.P., and have very high expectations, kind of like I am with Keiton (Page). I'm on top of Keiton all the time, and pushing Keiton all the time because I have such high expectations and believe that they can be difference markers. J.P. just has a tendency to relax at times," Ford added.
Olukemi has now scored in double figures in nine of the Cowboys' 15 games, and has scored 15 or more points in six games. He scored a career-high 21 points against Missouri State on Dec. 11, and had three games with seven rebounds. But he took his game to another level against the Wildcats.
"He's a good player, that's number one," K-State head coach Frank Martin said of Olukemi. "When you watched him on film you could see him coming on. It appears like to me that he's starting to feel a lot more comfortable with how they want him to play.
"I thought we defended well but I thought we gave him some offensive rebounds and put backs, and put him on the foul line, and when you let a good player see that ball go through the net it gets real hard. To his credit, he played very aggressive and was very assertive with his desire to go win the game."
Joining Olukemi in double figures for the Cowboys were Page (16 points despite fouling out with 3:45 remaining in the game), Marshall Moses (16 points and 9 rebounds), and Ray Penn (10 points, including a perfect 8-of-8 from the foul line).
Kansas State was led by Big 12 preseason player of the year Jacob Pullen with 20 points but he was only 4-of-11 from the field and made just one of five three-pointers.
The Cowboys play their next two games on the road as they travel to College Station, Texas to face Texas A&M on Wednesday and then make the trip to Boulder, Colo., for a Jan. 15 matchup against Colorado.